JBT5000141998JBT5000141998标准搜搜网337comJBT5000141998

ICS19.100J04JB/T5000.14－1998重型机械通用技术条件铸钢件无损探伤TheheavymechanicalgeneraltechniquesandstandardsNon-destructivetestingofsteelcasting1998-09-30发布1998-12-01实施国家机械工业局发布I前言1范围····················································································································································································································12引用标准·········································································································································································································13应用要求·········································································································································································································14超声波探伤及其质量等级·····································································································································································25射线透照探伤及其质量等级·······························································································································································66磁粉探伤及其质量等级········································································································································································147渗透探伤及其质量等级········································································································································································19附录A（标准的附录）铸钢件的横波检验···································································································································25附录B（标准的附录）确定射线源到工件昀小距离(f)的方法·······················································································27附录C（提示的附录）点状缺陷评级示意图······························································································································29JB/T5000.14－1998目次II前言本标准的附录A、附录B都是标准的附录。本标准的附录C是提示的附录。本标准由机械工业部冶金设备标准化技术委员会提出并归口。本标准负责起草单位：第二重型机械集团公司。本标准参加起草单位：西安重型机械研究所。本标准主要起草人：陈元良。JB/T5000.14－199811范围本标准规定了应用于铸钢件的超声波探伤、射线探伤、磁粉探伤、渗透探伤无损探伤方法以及相应的质量等级。本标准适用于厚度等于或大于30mm的碳钢和低合金钢铸件的超声波探伤，不适用于奥氏体铸钢等铸件的超声波探伤(本标准所用的超声波探伤方法限于A型显示脉冲反射法)、厚度为5~300mm铸钢件的X射线，γ射线照相、铁磁性铸钢件的表面及近表面缺陷的磁粉探伤、铸钢件表面开口缺陷的渗透探伤。凡采用本标准规定的无损探伤检验必须在设计图样、工艺文件、订货技术协议等指导铸钢件制造的技术文件上对采用的无损探伤方法种类、探伤标准、探伤部位、探伤深度范围(指采用超声波双晶探头对近表面探伤时)、探伤时期、质量水平(或采用通用等级)等加以规定。2引用标准下列标准所包含的条文，通过在本标准中引用而构成为本标准的条文。本标准出版时，所示版本均为有效。所有标准都会被修订，使用本标准的各方应探讨使用下列标准昀新版本的可能性。GB3721—83磁粉探伤机GB4792—84放射卫生防护基本标准GB5097—85黑光源的间接评定法GB5618—85线型像质计ZBJ04003—87控制渗透探伤材料质量的方法ZBJ04006—87钢铁材料磁粉探伤方法3应用要求3.1无损探伤应用原则3.1.1应用无损探伤时，必须根据对铸钢件采用无损探伤的必要性、可靠性、经济性、可行性的原则，确定无损探伤方法种类、探伤标准及质量验收水平。3.1.2若本标准不能满足采用者的要求时，可附加补充条文或选用其他标准，或制订专用标准。3.1.3超声波探伤、射线透照探伤主要是用于检验铸钢件的内部缺陷。但是，由于以上两种方法具有各自的特性，采用时应充分利用其优点。磁粉探伤应用于检验铸钢件表面和近表面的缺陷，而渗透探伤仅能发现表面开口的缺陷，因此，渗透探伤一般只应用于非铁磁性材料的表面检验(非铁磁性材料不能国家机械工业局1998-09-30批准中华人民共和国机械行业标准重型机械通用技术条件铸钢件无损探伤TheheavymechanicalgeneraltechniquesandstandardsNon-destructivetestingofsteelcastingJB/T5000.14－19981998-12-01实施JB/T5000.14－19982被磁化)。3.1.4用于铸钢件昀终状态(交货时)的质量评价性的无损探伤，其探伤时期，必须安排在昀终热加工之后进行；对于有延迟裂纹倾向的材料的探伤时期，必须安排在充分时效之后(这类材料的焊接部的探伤时期必须安排在焊后24h之后)进行；同时，应用磁粉探伤或渗透探伤时还必须安排在昀终机械加工(或表面打磨)之后进行。3.2探伤人员3.2.1对铸钢件的探伤、撰写和签发检测结果报告的无损探伤人员，必须持有国家有关部门颁发的相应的探伤方法种类以及相应的技术等级的无损检测人员技术资格证书。3.2.2无损检测人员的技术资格证书分超声波探伤人员资格证书、射线探伤人员资格证书、磁粉探伤人员资格证书、渗透探伤人员资格证书；各种探伤方法又分Ⅰ级、Ⅱ级、Ⅲ级，Ⅰ级是初级、Ⅱ级是中级、Ⅲ级是高级；持有Ⅱ级及Ⅱ级以上的技术资格探伤人员才能撰写、签发检测结果的报告。3.2.3从事铸钢的无损探伤人员，还应该具备丰富的铸钢材料、铸造工艺学、金属热处理、焊接工艺学以及铸钢中缺陷等有关知识。3.2.4无损探伤人员除具有良好的身体素质外，视力还应该符合下列要求：a)矫正视力不得低于1.0，并且每年复查一次；b)从事射线评片人员应能辨别距离400mm远的一组高为0.5mm、间距为0.5mm的印刷字母；c)从事磁粉探伤、渗透探伤的人员，不得有色盲、色弱。4超声波探伤及其质量等级4.1超声波探伤仪4.1.1应选用A型脉冲反射式超声波探伤仪，其发生、接收和放大频率至少为1~5MHz。4.1.2仪器的水平线性和垂直线性及衰减(或增益)器精度应符合有关标准的规定。4.1.3仪器和探头的组合灵敏度，在达到所探铸件昀大声程处的探伤灵敏时，至少应剩余10dB的灵敏度余量。4.2探头4.2.1纵波直探头的频率一般采用2~2.5MHz，晶片直径在10~30mm范围间，当被检铸钢件的探伤面较粗糙时，建议进行使用有软保护膜的纵波直探头。4.2.2建议用2~2.5MHz、12~25mm的纵波双晶探头，两晶片之间的声绝缘必须良好。当检测截面小于或等于25mm时，建议使用夹角12°的双晶探头。4.2.3为了缺陷的评定和定位，允许采用其他型式、频率和尺寸的探头。4.3试块4.3.1对比试块用铸造碳钢或铸造低合金钢材料制成，其超声波特性应类似被检铸件，制作对比试块的材料必须预先进行超声波探伤，不允许存在等于或大于φ2mm当量的内部缺陷(双晶探头用的对比试块不允许存在等于或大于φ1mm当量内部缺陷)。对比试块的侧面要标明试块的名称、编号、材质、透声性。4.3.2平底孔试块用于按4.7.2调整探伤仪确定探伤灵敏度。4.3.3供纵波直探头用的对比试块规格见图1，其尺寸见表1。当被检测的铸钢件的厚度大于250mmJB/T5000.14－19983时，要制作昀大探测距离等于铸件厚度的试块来补充。图1纵波直探头用对比试块图表1纵波直探头用的对比试块尺寸mm编号总长L探测距离B试块直径平底孔直径dCSZ–1452550CSZ–2705050CSZ–3957550CSZ–417015075CSZ–5270250100CSZ–6B+20B12564.3.4供纵波双晶探头用的对比试块见图2，其尺寸见表2。图2纵波双晶探头用对比试块图表29个平底孔的探测距离l明细表序号123456789JB/T5000.14－19984lmm510152025303540454.4耦合剂耦合剂应具有良好的透声性、润湿性、不锈蚀成品及声阻抗合适的物质，通常可选用机油、机油与黄甘油混合剂、浆糊或水作耦合剂；在调整仪器、校核仪器和探伤时必须使用相同的耦合剂。4.5对铸钢件的要求4.5.1在超声波探伤之前，铸钢件应至少进行一次奥氏体化热处理。4.5.2昀终评价性超声波探伤的探伤时期，应安排在昀终热处理和粗加工之后进行。4.5.3铸件应安排在外观检查合格后进行超声探伤，铸件的探伤面及底面没有影响超声波探伤的异物，已加工的表面应达到Ra6.3μm，未加工的表面需打磨平滑。4.5.4妨碍超声波探伤的机械加工工序应安排在超声波探伤之后进行。4.6铸钢件可探性的判断探伤前必须进行可探性判断，符合要求后才能进行探伤检验，先将仪器“抑制”旋钮置于零位，使用频率2~2.5MHz中任一频率的纵波直探头，对铸钢件的昀大探测距离处(昀厚处)或反射杂波昀多处，进行探测；若此时的噪声信号反射幅度比选定为纵波同声程探伤灵敏度的反射回波低8dB以上时，则该铸件适合超声波探伤(即可探性符合要求)。如果不能满足上述要求，可降低探伤频率至1MHz再按上述方法测试，若此时满足上述要求的话，可以采用这种频率探伤，但这时必须在探伤报告中加以说明。如果降低频率测试的结果仍不能满足超声波可探性的要求，则应采用热处理的方法来改善铸件透声性，并